1. Technical Field of the Invention
The present invention relates to wireless telecommunications networks. In particular, the present invention relates to geographical positioning methods and systems. More particularly, the present invention relates to techniques for optimizing wireless telecommunications networks utilizing geographical positioning information.
2. Description of the Related Art
Present-day mobile telephony has spurred rapid technological advances in both wireless and non-wireless areas. The telecommunications industry is a rapidly growing industry, with advances, improvements, and technological breakthroughs occurring on an almost daily basis. Many mobile telecommunications systems, among them the European GSM-system, have already passed through several basic development phases and system designers are now concentrating on further improvements to the systems, including system refinements and the introduction of optional services.
Most wireless telecommunication systems currently in use are implemented as cellular telephone networks. Cellular telephone networks typically are composed of a group of base stations connected to a centrally located switch. This centrally located switch is commonly referred to as a Mobile Switching Center (MSC). Base stations are usually spaced apart from each other by distances of between one-half and twenty kilometers. Each base station is assigned a number of two-way voice and control channels. The voice channels transmit voice signals to and from proximately located mobile stations, and transmit control information to and from these mobile stations, usually for the purpose of establishing a voice communications link.
A typical cellular telephone network also includes a group of interconnected mobile switching centers, which operate in association with a gateway mobile switching center through which the cellular telephone network interconnects with a conventional public switched telephone network (PSTN). In addition, at least one home location register (HLR) operates within the cellular telephone network. The HLR stores network subscriber information, including the identified location of current mobile stations within the network.
In response to an incoming call dialed to a mobile station, a signal is sent to the home location register requesting routing information through the network to the called mobile station. The home location register xe2x80x9clooks upxe2x80x9d the current location of the mobile station and contacts the currently serving mobile switching center to pre-route the call and retrieve a temporary location directory number, which is utilized to route the call through the cellular telephone network for delivery to the mobile station.
The serving mobile switching center retrieves from a visitor location register (VLR), the identification of the cell within which the called mobile station is currently located. The mobile switching center then instructs the base station associated with that particular cell to page the mobile station. Responding to the page, the mobile station requests assignment of a channel, and the network routes the call through the serving mobile switching center and over the assigned channel.
It is important to periodically optimize wireless telecommunications network functions and operations. Positioning information (e.g., geographical location of mobile units) can be utilized for wireless telecommunications network optimization and planning, such as xe2x80x9chot spotxe2x80x9d detection (i.e., for micro-cells or overlaid cells), handover/cell border optimization, detection of coverage holes, and so forth. Such geographical positioning information may also be utilized by vendors to improve existing radio network functionality, such as handover algorithms. The geographical positioning information can be obtained via GPS (Geographical Positioning System), Time-of-Arrival (TOA), and other geographical positioning techniques.
Wireless telecommunications network (i.e., radio network) optimization has traditionally been accomplished manually using cell-planning tools and cell test-drives. For example, when optimizing cell plan and handover borders within wireless cellular networks, data has traditionally been gathered by driving in a car within the cell border areas and recording positioning information utilizing a GPS receiver installed in the test-drive vehicle. The recorded data is then correlated with the position provided manually by the GPS receiver. This process requires extensive cell test-drives and is known to be very tedious and costly for the network operators or optimization team. Such optimization methods typically cover only the drive route followed by the test-drive vehicle and do not provide all positioning information. Thus, such methods are limited because they can not be utilized for all coverage areas or types of radio network optimization (e.g., xe2x80x9chot spotxe2x80x9d detection, detection of coverage holes or geographical information on handovers, and so forth).
From the foregoing, it can be appreciated that a need exists for a reliable method and system that would permit radio network operators or optimization teams to efficiently utilize geographical positioning information to optimize telecommunications operations and functions within radio networks. It is believed that the method and system described herein solves this problem.
It is therefore one object of the present invention to provide an improved wireless telecommunications network.
It is another object of the present invention to provide a method and system for optimizing telecommunications operations within wireless telecommunications networks.
It is still another object of the present invention to provide a method and system for efficiently optimizing and planning telecommunications operations within wireless telecommunications networks, utilizing geographical positioning information.
The above and other objects are achieved as is now described. A method and system are disclosed for optimizing mobile telecommunications networks utilizing geographical positioning information. Initially, a particular telecommunications event, such as a handover event, call set-up event, or a dropped call event, is designated, such that an occurrence of the particular telecommunications event automatically triggers geographical positioning of a mobile unit within a mobile telecommunications network. Other particular telecommunications events designated as such include high bit error rate events, wherein the bit error rate is greater than a predefined threshold. A geographical positioning request is then transmitted to a mobile location center within the telecommunications network, in response to an occurrence of the particular telecommunications event.
Thereafter, geographical positioning information associated with the particular telecommunications event and the mobile unit is determined, in response to the transmission of the geographical positioning request to the mobile location center. The geographical positioning information is thereafter stored in a database within the mobile telecommunications network. The geographical positioning information can thereafter be analyzed in order to optimize telecommunications operations within the mobile telecommunications network. The geographical positioning information can be used for network optimization, such as xe2x80x9chot spotxe2x80x9d detection for micro cells overlaid cells within a cellular telecommunications network, handover and cell border optimization, and detection of coverage holes. Such geographical positioning information can also be utilized to improve network functionality, such as handover algorithms.